package chapter4;

import java.io.IOException;
import java.util.concurrent.TimeoutException;

public class ClassB implements InterfaceA, InterfaceB {

    public String m1() {
        return null;
    }

    public String m2() {
        return "0";
    }
    
    //must throws the sub-type of both TimeoutException and IOException
    public void m3() throws TimeoutException, IOException {
        
    }

}
